Relapse-Prevention Booklets as Adjunct to a Tobacco Quitline Project Summary Tobacco smoking is the leading preventable cause of cancer and coronary heart disease, and it is the primary cause of premature death due to cancer. Thus, great potential for prevention of these diseases lies with efforts toward long-term cessation of smoking. In response to this public health challenge, tobacco cessation quitlines have now been developed in every US state, and recent meta-analyses indicate that the services provided by quitlines significantly improve cessation rates compared to control conditions. Unfortunately, smoking cessation is characterized by high rates of subsequent relapse, with approximately 95% of self-quitters relapsing within a year of their cessation attempt. Relapse rates are slightly less among those receiving treatment in a formalized program, such as a quitline, yet the norm is that the vast majority of smokers will at some point relapse back to smoking. Previous research has found that a series of 8 Forever Free relapse-prevention booklets mailed to individuals who recently quit smoking significantly reduces rates of smoking relapse through at least 2 years of follow-up, and that this intervention is highly cost-effective. Because of these findings, the Forever Free booklets have been promoted and distributed by NCI. However, these results were based on efficacy trials with self-selected former smokers who were recruited via reactive recruitment strategies. A controlled effectiveness trial of the Forever Free relapse-prevention booklets with callers to a state quitline would test the effect of the intervention on a more general population of quitters. Moreover, given the recent growth in quitline usage, an effective minimal intervention to prevent relapse among individuals who quit smoking using a quitline would have extremely high public health significance. The proposed study is a collaboration between researchers who developed the relapse-prevention intervention, at the H. Lee Moffitt Cancer Center in Tampa, Florida, and those associated with the New York State Smokers' Quitline (NYSSQL), at Roswell Park Cancer Institute in Buffalo, New York, one of the busiest quitllines in the US. Approximately 3400 quitline clients will be randomized to one of three conditions at the point of their 2-week follow-up call. One-third will be randomized to a Usual Care (UC) condition, which will receive regular quitline services. One-third will be randomized to a Repeated Mailings (RM) condition, which will receive the 8 Forever Free booklets sent by mail at regular intervals over a period of 12 months. And one- third will be randomized to a Massed Mailings (MM) condition, which will receive all 8 booklets in a single mailing. The primary specific aims are (1) to test the effectiveness of a self-help, relapse-prevention intervention (Forever Free booklets) as an adjunct to a state telephone quitline; (2) to compare two different booklet distribution schedules that have been supported in previous research; and (3) to calculate and compare the cost-effectiveness of the interventions. Such an effectiveness study represents the final step in intervention development and validation before widespread dissemination via state quitlines can be justified.